Bolton secured a vital away victory against relegation rivals West Ham with two goals inside the opening 16 minutes from Kevin Davies and Jack Wilshere.

Davies was magnificent throughout and his powerful header gave Bolton the lead before he turned provider, robbing James Tomkins of the ball to tee up 18-year-old Wilshere.

West Ham mounted a spirited comeback after Bolton had Tamir Cohen sent off for two bookable offences in the second half and Alessandro Diamanti curled in a late consolation.

Both sides hit the bar in a frantic finale but Bolton held on for a sixth straight victory over West Ham - and their third this season - which takes them above the Hammers in the table.

All the pre-match statistics had pointed to a home win. Bolton had not won on their travels in six months or scored away from the Reebok Stadium in over seven hours of football.

West Ham, meanwhile, had not conceded a goal at Upton Park in four Premier League matches and boasted England duo Matthew Upson and Robert Green at the back.

But Bolton are West Ham's bogey team and turned those records upside down inside 16 minutes, helped by some calamitous home defending.

West Ham could not handle Davies' physical presence all afternoon and he put Bolton ahead with a powerful header after rising above Julien Faubert to meet Lee Chung-Yong's cross.

Tomkins was all at sea at the heart of West Ham's defence, unable to cope with Davies and Johan Elmander, and it was his mistake which gifted Bolton their second just six minutes later.

The England Under-21 international tried to shepherd the ball out of play for a goal-kick but was caught out by Davies, who clipped a cross into the box.

Cohen, in the side after Stuart Holden broke his leg in midweek, knocked the ball down to Wilshere who beat Green from close range with an acrobatic finish and became the youngest Premier League scorer of the season.

West Ham may have been poor at the back but they were lively going forward and came close with two Diamanti free-kicks from the edge of the box.

The Italian curled an early effort onto the roof of the net after Parker's surging run had been checked.

After Bolton's double strike, Paul Robinson was booked for a trip on Radoslav Kovac and Diamanti tried his luck again from a similar position.

But Bolton keeper Jussi Jaaskelainen was equal to Diamanti's powerful drive and he then denied Guillermo Franco, who had pounced on the rebound.

With the Upton Park crowd growing increasingly agitated, West Ham began to lose their composure going forward.

Carlton Cole had the best chance, racing into the box to meet Scott Parker's through-ball with only Jaaskelainen to beat.

But the England striker took too many touches, allowing Sam Ricketts time to race back and execute a perfectly timed cover tackle.

Parker wasted another promising opportunity with poor control before Diamanti drilled a cross into the box but Zat Knight cleared off the line after a goalmouth scramble.

West Ham's defending was almost comical at times, drawing howls of derision from the stands.

Jonathan Spector, playing out of position at left-back, allowed Lee a free shot at the far post but the Bolton winger skewed it wide.

And a better striker than Elmander might have had a first-half hat-trick for Bolton.

The Swede saw one effort blocked by Green, he drilled another into the side netting and then squandered his best chance of the half from six yards out.

Elmander lost Tomkins in the box and was picked out by Davies' right-wing cross but, under no pressure, he sent his shot over the bar.

West Ham brought on Kieron Dyer early in the second half after Faubert strained a muscle and he almost made an immediate impact, latching onto Cole's knock-down but shooting over the bar.

Fabrice Muamba was booked for a foul on Parker to offer Diamanti a third chance from the edge of the box, but his free-kick hit the wall and bounced clear.

Bolton were reduced to 10 men just after the hour mark after Cohen collected two bookings inside nine minutes, the second for a mindless trip on the industrious Parker.

Diamanti finally created a breakthrough for West Ham, curling a neat shot past Jaaskelainen to give some credence to the rather bizarre decision to make him man of the match.

In a frantic finish, Davies hit the bar after a counter-attack from Knight before Junior Stanislas rattled the woodwork.